This is a pilot study of non-diabetic subjects who have fasting glucose levels greater than 50 mU/ml and who are obese. Each subject will be given metformin, 500-1000 mg twice a day for three months. It is hypothesized that these subjects will experience weight loss and lowered serum insulin levels to a greater degree than subjects in a previous study who were on a specified diet or exercise regimen. By reducing obesity and hypercholesterolism, intervention with metformin could decrease the potential to develop type II diabetes. Taking metformin does not appear to result in significant weight loss. However, serum insulin levels are markedly reduced by the drug. Furthermore, investigators have noted significant improvement of acanthosis nigricans in all patients while taking metformin.